This invention relates to packaging methods in general and, in particular, to methods for reducing heat loss of hot pizzeria pizza shipped in corrugated box packaging.
Each year the pizzeria industry sells millions of hot pizzas in corrugated boxes for delivery and carry-out. The eating enjoyment of these pizzas is, in large part, determined by the temperature of the product at the time the pizza-eater consumes it. So providing for a hotter boxed pizza is a priority of many pizza companies.
Most delivery/carry-out pizza companies use a particular shipping method, which we call the xe2x80x9cconventional shipping method,xe2x80x9d involving a conventional corrugated pizza box similar in structure to the box shown in Anatro U.S. Pat. No. 5,209,392 (Recyclable Pizza Box) granted May 11, 1993. Referencing the component numerals shown in FIGS. 2, 3, and 6 of Anatro, the conventional corrugated pizza box has a double-panel front wall structure comprising an outer panel (48) and an inner panel (50). Along the bottom edge of the outer panel are two tabs (60, 62). The purpose of these tabs is to provide slots in the bottom side of the box when the blank is erected into the box.
The conventional shipping method involves the steps of (a) placing a recently-cooked (i.e., hot) pizza into the conventional corrugated pizza box, (b) transporting the conventional corrugated pizza box loaded with hot pizza to an outlying place of consumption, such as a pizza-eater""s residence, and, once there, (c) setting the pizza-loaded box onto a cool support surface, such as a table or counter. While sitting on the table the bottom panel of the box contacts the tabletop. This contact results in conduction of heat from the pizza through the box""s bottom panel and into the table. That, in turn, contributes to rapid cooling of the pizza. Therefore, it would be desirable to eliminate contact of the bottom panel of corrugated pizza box packaging with the tabletop in pizza consumers"" residences and, thereby, slow down the rate of cooling of the pizza shipped in corrugated box packaging.
In viewing the conventional corrugated pizza box (i.e., FIGS. 2 and 3 of Anatro), it might be concluded that, due to the front wall tabs (60, 62), the bottom panel (14) of this box would be held above a support surface that the box would happen to be sitting upon. However, this conclusion is incorrect. When this box is loaded with hot pizza, the bottom panel warps downward due to the heat and moisture of the hot pizza. This warping effect results in the bottom panel coming into contact with any support surface the box might be sitting upon. Hence, in the loaded conventional corrugated pizza box the tabs (60, 62) are ineffective in keeping a downward-warping bottom panel of the box free of contact with a cool support surface below.
The most common support surface is a tabletop, or countertop. However, other cool surfaces which the pizza-loaded corrugated box might contact include (a) the floor of an automotive vehicle, (b) the cover of another pizza-loaded box, and (c) the inside surface or support platform of a delivery pizza holding device, such as a delivery bag or rigid foam box. It would be desirable to eliminate contact of the bottom panel of the pizza-loaded corrugated box with these surfaces, as well.
Since some pizza orders involve two pizzas, the conventional shipping method also might involve stacking one pizza-loaded corrugated box on top of another. Lastly, for delivery pizza, the method often involves inserting the pizza-loaded box into a heat-retentive holding device such as a delivery bag.
In addition to heat loss, a further problem occurs when two loaded corrugated boxes are stacked. The bottom panel of the upper box is put into contact with the cover of the lower box. This results in condensation build-up within the cover of the lower box, making for an undesirably soggy box top. So it also would be desirable to have a method of shipping hot pizza whereby the bottom panel of the upper corrugated box is kept free of contact with the cover of the lower box.
In short, it would be desirable to have a method of shipping recently-cooked pizzeria pizza in corrugated box packaging wherein the loss of heat from the pizza through the bottom panel of the box is reduced, thereby keeping the pizza hot for a longer time.
In addition to the conventional shipping method, the prior art contains several other pizza shipping methods. They include those disclosed in Kuchenbecker U.S. Pat. No. 4,096,948 (Cook-in Carton with Integral Removable Section and Blank Therefor) granted Jun. 27, 1978; Faller U.S. Pat. No. 4,260,060 (Food Carton for Microwave Heating) granted Apr. 7, 1981; Peleg et al. U.S. Pat. No. 5,077,455 (Easy Open Microwave Susceptor Sleeve for Pizza and the Like) granted Dec. 31, 1991; France U.S. Pat. No. 5,253,800 (Pizza Tray) granted Oct. 19, 1993; Valdman et al. U.S. Pat. No. 5,423,477 (Pizza Box) granted Jun. 13, 1995; and Correll U.S. Pat. No. 5,549,241 (Interlock for Stackable Boxes) granted Aug. 27, 1996. In addition, there""s a rigid foam insulating tray, called the PIZZA CADDY(copyright) insulating tray, which adhesively secures to the bottom of a pizza box for reducing condensation, catching leakage, and preventing burning of the legs when carrying it on one""s lap. However, each of these methods is either inapplicable to the situation and problems involved in shipping hot pizzeria pizza in corrugated box packaging or has a major drawback as regards the pizzeria industry. Following are the particulars.
The Kuchenbecker method does not pertain to shipping hot pizzeria pizza but, instead, involves the microwave heating of frozen pizza. The carton is a glued-corner (i.e., fastened-corner) carton with interior openings in the bottom panel. The purpose of the openings is to allow gases to dissipate from the carton during microwaving. The carton has two panels glued to the bottom of the box which are folded downward just prior to microwaving to raise the bottom of the box above the floor of the microwave oven, thereby facilitating ventilation of the carton. This method is inapplicable to the situation of the pizzeria industry and to shipping hot pizzeria pizza in corrugated box packaging.
The Faller method does not pertain to shipping hot pizzeria pizza but, like the Kuchenbecker method, involves the microwave heating of frozen pizza. The carton is a glued-corner (i.e., fastened-corner) carton having a bottom panel with interior openings and also downward-projecting and upward-projecting tabs extending from the bottom panel. During shipment, these tabs are disposed coplanar with the bottom panel and, just prior to microwaving, the tabs are moved into a perpendicular disposition to the bottom panel by removing a glued-on film strip. The purpose of the openings and tabs is to allow gases to dissipate from the carton during microwaving and also to raise the pizza above the bottom panel of the box. As with the Kuchenbecker method, this method is inapplicable to the situation of the pizzeria industry and to shipping hot pizzeria pizza in corrugated box packaging.
The Peleg et al. method does not pertain to shipping hot pizzeria pizza but, like the Kuchenbecker and Faller methods, involves the microwave heating of frozen pizza. This method does not involve a carton, per se, but actually involves a sleeve that""s open on opposing ends. The sleeve is shipped in flat (i.e., blank) format and the consumer erects it and places the pizza within it just prior to microwaving. The sleeve is made of microwave susceptor material to facilitate heating of the pizza and has tabs projecting downward from opposing sides of the sleeve to raise the bottom panel of the sleeve above the floor of the microwave oven during heating. This creates a space between the sleeve and floor of the oven which facilitates convective flow of air underneath the sleeve. As with the Kuchenbecker and Faller methods, this method is inapplicable to the situation of the pizzeria industry and to shipping hot pizzeria pizza in corrugated box packaging.
The France method does not involve a box but, rather, involves serving a pizza on an open tray having tabs projecting downward through interior openings in the bottom panel. This method doesn""t apply to the process of shipping hot pizza in a closed container or box and, as a result, does not apply to improving heat-retention of boxed pizza.
The Valdman et al. method requires a molded container, typically made of molded paper pulp, and therefore is inapplicable to the process of shipping pizza in corrugated box packaging. This carton has a circular perimeter edge and a raised bottom panel. Being a molded container, the manufacturing process for making this carton is slow and, therefore, expensive; making this pizza-shipping method an unfeasible and undesirable method for pizzerias and also inapplicable to the situation involving corrugated box packaging.
The Correll method (U.S. Pat. No. 5,549,241) involves packing a pizza in a box having four downward-projecting tabs that extend about six millimeters below the bottom panel of the box. However, as with the conventional corrugated pizza box, these tabs do not extend far enough below the bottom panel to hold the bottom of a large E-flute corrugated box above a support surface once the bottom panel warps downward due to the steam of the hot pizza. Therefore, this method provides little or no reduction in conductive heat loss through the bottom panel of the box. Hence, it provides little or no heat-retentive benefit.
As previously discussed, the conventional pizza box (illustrated by the Anatro box) used in the conventional shipping method involves two downward-projecting tabs that extend about six millimeters below the bottom panel of the box. However, like the above-described Correll method, the tabs involved in the conventional shipping method do not extend far enough below the bottom panel to hold the bottom of a large E-flute corrugated box above a support surface once the bottom panel warps downward due to the heat and moisture of the hot pizza. Therefore, this method provides little or no reduction in conductive heat loss through the bottom panel of the box.
The PIZZA CADDY(copyright) insulating tray method does not actually pertain to a box, per se, but instead involves sticking a rigid foam insulating tray to the bottom of a box. As such, it""s time-consuming and also expensive, which are major drawbacks to many pizza companies.
So, there has remained a problem of how to easily and economically reduce heat loss of hot pizzeria pizza when that pizza is shipped in corrugated box packaging. There has also remained a problem of how to stack two loaded corrugated boxes so that there is no condensation build-up on the bottom and top panels of the upper and lower boxes, respectively. These problems have not been solved by the prior art but are solved by my invention. By solving these problems, a pizza company can provide economical corrugated boxed pizza that stays hot for a longer period of time, thereby providing a more-enjoyable pizza-eating experience to its customers, and can do it without incurring substantial additional packaging cost and operational inconvenience.
My invention is a method for reducing heat loss of hot pizzeria pizza shipped in corrugated box packaging. The method comprises the step of placing a recently-cooked pizzeria pizza into a thermal-leg-equipped one-piece corrugated box, whereby a pizza-loaded thermal-leg-equipped corrugated box is created. The method solves two particular problems associated with the conventional shipping method for hot pizza.
First, the method solves the problem of a downward-warping bottom panel of a loaded corrugated pizza box coming into contact with a cool support surface upon which the box might be sitting.
Second, the method solves the problem of condensation build-up between the cover of a lower box and the bottom panel of an upper box of two stacked loaded corrugated pizza boxes.
Neither of these two problems is solved by the prior art of pizza shipping methods. A complete understanding of the invention can be obtained from the detailed description that follows.
Accordingly, the main object of my invention is a reduction in heat loss of recently-cooked pizzeria pizza shipped in corrugated box packaging. A secondary object is a reduction in condensation build-up on a cover of a corrugated box when two loaded pizza boxes are stacked one on top of the other.
The advantages of my invention are (a) hotter pizza for pizza consumers receiving pizza in corrugated box packaging (without incurring substantial additional cost and operational inconvenience for pizza companies), and (b) pizza delivered in a dryer corrugated box when multiple pizza boxes are stacked.
Further objects and advantages of the invention will become apparent from consideration of the following detailed description, related drawings, and appended claims.